Effects of Central Administration of Glutamine and Alanine on Feed Intake and Hypothalamic Expression of Orexigenic and Anorexigenic Neuropetides in Broiler Chicks  

作　　者：Khondowe Paul WANG Song-bo CHEN Sheng-feng YU Jian-jian ZHU Xiao-tong WANG Li-na GAO Ping XI Qian-yun ZHANG Yong-liang SHU Gang JIANG Qing-yan 

机构地区：[1]College of Animal Sciences, South China Agricultural University, Guangzhou 510642, P.R.China [2]School of Natural Sciences, Department of Biological Sciences, University of Zambia, P,O. Box 32379, Lusaka, Zambia

出　　处：《Journal of Integrative Agriculture》2012年第7期1173-1180,共8页农业科学学报（英文版）

基　　金：the National Basic Research Program of China (2009CB941601);the Joint Funds of the National Natural Science Foundation of China (u0731004);the National Natural Science Foundation of China(30871845, 30901058 and 30972157);the Natural Science Foundation of Guangdong Province of China(9451064201003790 and 9151064201000056);the National Public Benefit (Agricultural) Research Foundation of China(201003011);the Specialized Research Fund for the Doctoral Program of Higher Education of China(20094404120012)

摘　　要：Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intake and the mRNA expression levels of hypothalamic neuropeptides involved in feed intake regulation in broiler chicks. L-Glutamine or L- alanine was intra-cerebroventricularly （ICV） administered to 4-d-old broiler chicks and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotropin releasing factor （CRF）. Our results showed that ICV administration of L-glutamine （0.55 or 5.5 pmol） significantly increased feed intake up to 2 h post-administration period and the hypothalamic NPY mRNA expression levels, while it markedly decreased hypothalamic POMC and CRF mRNA expression levels. In contrast, ICV administration of L-alanine （4 lamol） significantly decreased feed intake for the first 0.5 h post-administration period, and reduced the hypothalamic AgRP mRNA expression levels, while it remarkablely enhanced the mRNA expression levels of MC4R and CRF. These findings suggested that L-glutamine and L-alanine could act within the hypothalamus to influence feed intake in broiler chicks, and that both orexigenic and anorexigenic neuropeptide genes might contribute directly to these effects.Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intake and the mRNA expression levels of hypothalamic neuropeptides involved in feed intake regulation in broiler chicks. L-Glutamine or L- alanine was intra-cerebroventricularly （ICV） administered to 4-d-old broiler chicks and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotropin releasing factor （CRF）. Our results showed that ICV administration of L-glutamine （0.55 or 5.5 pmol） significantly increased feed intake up to 2 h post-administration period and the hypothalamic NPY mRNA expression levels, while it markedly decreased hypothalamic POMC and CRF mRNA expression levels. In contrast, ICV administration of L-alanine （4 lamol） significantly decreased feed intake for the first 0.5 h post-administration period, and reduced the hypothalamic AgRP mRNA expression levels, while it remarkablely enhanced the mRNA expression levels of MC4R and CRF. These findings suggested that L-glutamine and L-alanine could act within the hypothalamus to influence feed intake in broiler chicks, and that both orexigenic and anorexigenic neuropeptide genes might contribute directly to these effects.

关 键 词：L-GLUTAMINE L-ALANINE intracerebroventricular （ICV） feed intake hypothalamus 

分 类 号：S831.5[农业科学—畜牧学]